From 8de98402652c01839ae321be6cb3054cf5735d83 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Fri, 25 Nov 2005 09:59:46 +1100 Subject: [PATCH] USB: Fix USB suspend/resume crasher (#2) This patch closes the IRQ race and makes various other OHCI & EHCI code path safer vs. suspend/resume. I've been able to (finally !) successfully suspend and resume various Mac models, with or without USB mouse plugged, or plugging while asleep, or unplugging while asleep etc... all without a crash. Alan, please verify the UHCI bit I did, I only verified that it builds. It's very simple so I wouldn't expect any issue there. If you aren't confident, then just drop the hunks that change uhci-hcd.c I also made the patch a little bit more "safer" by making sure the store to the interrupt register that disables interrupts is not posted before I set the flag and drop the spinlock. Without this patch, you cannot reliably sleep/wakeup any recent Mac, and I suspect PCs have some more sneaky issues too (they don't frankly crash with machine checks because x86 tend to silently swallow PCI errors but that won't last afaik, at least PCI Express will blow up in those situations, but the USB code may still misbehave). Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-pci.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) (limited to 'drivers/usb/host/ehci-pci.c') diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c index 441c26064b4..14fff5714c1 100644 --- a/drivers/usb/host/ehci-pci.c +++ b/drivers/usb/host/ehci-pci.c @@ -228,14 +228,36 @@ static int ehci_pci_reset(struct usb_hcd *hcd) static int ehci_pci_suspend(struct usb_hcd *hcd, pm_message_t message) { struct ehci_hcd *ehci = hcd_to_ehci(hcd); + unsigned long flags; + int rc = 0; if (time_before(jiffies, ehci->next_statechange)) msleep(10); + /* Root hub was already suspended. Disable irq emission and + * mark HW unaccessible, bail out if RH has been resumed. Use + * the spinlock to properly synchronize with possible pending + * RH suspend or resume activity. + * + * This is still racy as hcd->state is manipulated outside of + * any locks =P But that will be a different fix. + */ + spin_lock_irqsave (&ehci->lock, flags); + if (hcd->state != HC_STATE_SUSPENDED) { + rc = -EINVAL; + goto bail; + } + writel (0, &ehci->regs->intr_enable); + (void)readl(&ehci->regs->intr_enable); + + clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); + bail: + spin_unlock_irqrestore (&ehci->lock, flags); + // could save FLADJ in case of Vaux power loss // ... we'd only use it to handle clock skew - return 0; + return rc; } static int ehci_pci_resume(struct usb_hcd *hcd) @@ -251,6 +273,9 @@ static int ehci_pci_resume(struct usb_hcd *hcd) if (time_before(jiffies, ehci->next_statechange)) msleep(100); + /* Mark hardware accessible again as we are out of D3 state by now */ + set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); + /* If CF is clear, we lost PCI Vaux power and need to restart. */ if (readl(&ehci->regs->configured_flag) != FLAG_CF) goto restart; -- cgit v1.2.3-70-g09d2 From 8926bfa7462d4c3f8b05cca929e0c4bcde93ae38 Mon Sep 17 00:00:00 2001 From: David Brownell Date: Mon, 28 Nov 2005 08:40:38 -0800 Subject: [PATCH] USB: ehci fixups Rename the EHCI "reset" routine so it better matches what it does (setup); and move the one-time data structure setup earlier, before doing anything that implicitly relies on it having been completed already. From: David Brownell Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-pci.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) (limited to 'drivers/usb/host/ehci-pci.c') diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c index 14fff5714c1..13f73a836e4 100644 --- a/drivers/usb/host/ehci-pci.c +++ b/drivers/usb/host/ehci-pci.c @@ -121,8 +121,8 @@ static int ehci_pci_reinit(struct ehci_hcd *ehci, struct pci_dev *pdev) return 0; } -/* called by khubd or root hub (re)init threads; leaves HC in halt state */ -static int ehci_pci_reset(struct usb_hcd *hcd) +/* called during probe() after chip reset completes */ +static int ehci_pci_setup(struct usb_hcd *hcd) { struct ehci_hcd *ehci = hcd_to_ehci(hcd); struct pci_dev *pdev = to_pci_dev(hcd->self.controller); @@ -141,6 +141,11 @@ static int ehci_pci_reset(struct usb_hcd *hcd) if (retval) return retval; + /* data structure init */ + retval = ehci_init(hcd); + if (retval) + return retval; + /* NOTE: only the parts below this line are PCI-specific */ switch (pdev->vendor) { @@ -154,7 +159,8 @@ static int ehci_pci_reset(struct usb_hcd *hcd) /* AMD8111 EHCI doesn't work, according to AMD errata */ if (pdev->device == 0x7463) { ehci_info(ehci, "ignoring AMD8111 (errata)\n"); - return -EIO; + retval = -EIO; + goto done; } break; case PCI_VENDOR_ID_NVIDIA: @@ -207,9 +213,8 @@ static int ehci_pci_reset(struct usb_hcd *hcd) /* REVISIT: per-port wake capability (PCI 0x62) currently unused */ retval = ehci_pci_reinit(ehci, pdev); - - /* finish init */ - return ehci_init(hcd); +done: + return retval; } /*-------------------------------------------------------------------------*/ @@ -344,7 +349,7 @@ static const struct hc_driver ehci_pci_hc_driver = { /* * basic lifecycle operations */ - .reset = ehci_pci_reset, + .reset = ehci_pci_setup, .start = ehci_run, #ifdef CONFIG_PM .suspend = ehci_pci_suspend, -- cgit v1.2.3-70-g09d2